Audi 5000
The title for the most unsafe car on the road is crowded because there were many failures. But perhaps one of the most surprising failures was the Audi 5000. You’ll seldom hear about Audi building a questionable vehicle. Especially considering the 5000 was released during the company’s heyday of Quattro engineering (via The Truth About Cars).

The major flaw with the Audi 5000 was that the car decelerated and accelerated without the driver being in control. There were dozens of catastrophic crashes involving the 5000. Audi never fixed the problem with the 5000, and the car was discontinued shortly after being released to the public.